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Re: incompatible environment variable names
On Aug 4 13:59, Nellis, Kenneth wrote:
> > From: Steven Collins
> > On Wed, Aug 4, 2010 at 10:23, Nellis, Kenneth wrote:
> > > [...]
> > > So, Windows has no problem with + symbols in variable names, but
> > > bash does, kinda sorta:
> > > [...]
> >
> > From the bash man page:
> <snip/>
> >
> > Hench bash does not support the plus character in a variable name and
> > no amount of finagling is going to fix it.
>
> Well, *somehow* it got into the Cygwin environment, and cygwin.bat directly
> invokes bash, so I interpret this as bash creating the Cygwin environment.
> Where is the hole in this logic?
The environment is converted by the Cygwin DLL, not by bash. And, even
though the '+' character is *theoretically* allowed in a POSIX
environment variable name(*), neither bash nor tcsh(**) handles it
transparently as part of a variable name. This is *not* a Cygwin
problem(**).
(*) http://www.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html
Accentuation added by me:
[...]
Environment variable names used by the utilities in the Shell and
Utilities volume of POSIX.1-2008 consist solely of uppercase letters,
digits, and the <underscore> ( '_' ) from the characters defined in
[ASCII] and do not begin with a digit. Other characters *may* be
permitted by an implementation; applications *shall* tolerate the
presence of such names.
(**) On Linux:
tcsh$ $ echo $version
tcsh 6.17.00 (Astron) 2009-07-10 (x86_64-unknown-linux) options wide,nls,dl,al,kan,rh,color,filec
tcsh$ setenv QNX_VISUAL_C++_PATH foo
tcsh$ env | grep QN
QNX_VISUAL_C++_PATH=foo
tcsh$ echo $QNX_VISUAL_C++_PATH
QNX_VISUAL_C: Undefined variable.
tcsh$ echo ${QNX_VISUAL_C++_PATH}
Missing }.
tcsh$ echo "$QNX_VISUAL_C++_PATH"
QNX_VISUAL_C: Undefined variable.
Corinna
--
Corinna Vinschen Please, send mails regarding Cygwin to
Cygwin Project Co-Leader cygwin AT cygwin DOT com
Red Hat
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